[PATCH] choose_new_parent: remove unused arg, sanitize exit_state check

'child_reaper' arg is not used in choose_new_parent().

"->exit_state >= EXIT_ZOMBIE" check is a leftover, was
valid when EXIT_ZOMBIE lived in ->state var.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

kernel/exit.c

@@ -538,13 +538,13 @@ static void exit_mm(struct task_struct * tsk)
 	mmput(mm);
 }
 
-static inline void choose_new_parent(task_t *p, task_t *reaper, task_t *child_reaper)
+static inline void choose_new_parent(task_t *p, task_t *reaper)
 {
 	/*
 	 * Make sure we're not reparenting to ourselves and that
 	 * the parent is not a zombie.
 	 */
-	BUG_ON(p == reaper || reaper->exit_state >= EXIT_ZOMBIE);
+	BUG_ON(p == reaper || reaper->exit_state);
 	p->real_parent = reaper;
 }
 
@@ -645,7 +645,7 @@ static void forget_original_parent(struct task_struct * father,
 
 		if (father == p->real_parent) {
 			/* reparent with a reaper, real father it's us */
-			choose_new_parent(p, reaper, child_reaper);
+			choose_new_parent(p, reaper);
 			reparent_thread(p, father, 0);
 		} else {
 			/* reparent ptraced task to its real parent */
@@ -666,7 +666,7 @@ static void forget_original_parent(struct task_struct * father,
 	}
 	list_for_each_safe(_p, _n, &father->ptrace_children) {
 		p = list_entry(_p,struct task_struct,ptrace_list);
-		choose_new_parent(p, reaper, child_reaper);
+		choose_new_parent(p, reaper);
 		reparent_thread(p, father, 1);
 	}
 }